webpack.client.js

const path = require('path');

module.exports = {
    target: 'node',
    entry: './src/client/index.js',
    output: {
        filename: 'client_bundle.js',
        path: path.resolve(__dirname, 'build/public'),
        publicPath: '/build/public'
    },
    module: {
        rules: [
            {
                test: [/\.svg$/, /\.gif$/, /\.jpe?g$/, /\.png$/],
                loader: "file-loader",
                options: {
                    name: "build/media/[name].[ext]",
                    publicPath: url => url.replace(/build/, "")
                }
            },
            {
                test: /\.js$/,
                loader: 'babel-loader',
                exclude: '/node_modules/',
                options: {
                    presets: [
                        '@babel/preset-react',
                        '@babel/env'
                    ],
                    "plugins": [
                        "@babel/plugin-proposal-class-properties"
                    ]
                }
            },
            {
                test: /\.css$/i,
                loader: ['style-loader', 'css-loader']
            }
        ]
    }
}